1. Field of the Invention
The present invention relates to a freewheel arrangement, in particular for a guide wheel of a hydrodynamic torque converter, which freewheel arrangement essentially permits a relative rotation between two elements in only one relative rotational direction with respect to one another about an axis of rotation. At least one pawl is pivotably supported on a first of the two elements and has a pawl section which can come into contact with a blocking surface of the second of the two elements.
2. Description of the Related Art
Such a freewheel arrangement is known, for example, from U.S. Pat. No. 5,070,978. The known freewheel arrangement has a plurality of pawls, which are sequential to one another in the peripheral direction, which are pivotally supported on one of the elements and which, by means of their respective locking sections, engage radially outward for interaction with the other element. During the manufacture of such freewheel arrangements, the individual pawls must be manufactured with a high level of precision. In order to obtain the necessary torque transmission capacity in the blocking direction, furthermore, a plurality of pawls must, as already described, be provided sequentially to one another in the peripheral direction. This leads to a substantial expenditure of labor both in the process of manufacturing the individual pawls and in the process of assembly of such a freewheel arrangement.
The object of the present invention is to provide a freewheel arrangement with a favorable cost and easily manufactured design which achieves a high torque transmission capability in the locking direction.
According to the invention, this object is achieved by a freewheel arrangement, in particular for a guide wheel of a hydrodynamic torque converter, which freewheel arrangement essentially permits a relative rotation between two elements in only one relative rotational direction with respect to one another about an axis of rotation. At least one pawl is pivotably supported on a first of the two elements and has a pawl section which can come into contact with a blocking surface of the second of the two elements.
In this arrangement, provision is then additionally made for the at least one pawl to comprise a plurality of pawl plate elements.
The pawls are made up from a plurality of plate elements so that relatively thick pawls (viewed in the direction of their pivoting axis) are finally obtained which, as compared with conventional pawls formed from one body, provide a distinctly greater interaction surface for the interaction with a respective blocking surface. This, in turn, results in a reduction of the surface pressure with the result that the number of pawls to be employed to obtain the necessary torque transmission capacity can be distinctly reduced relative to the prior art.
As an example, the pawl plate elements can be sequentially arranged relative to one another in the direction of a pivoting axis about which the at least one pawl is pivotably supported on the first element. To further simplify the joining together of a freewheel arrangement according to the invention, the pawl plate elements are preferably permanently connected together. This can be done, for example, by bonding, welding or forming.
The individual pawl plate elements can, for example, be formed from sheet material, i.e. they can be manufactured by stamping techniques in a cost-favorable manner but still provide a very stable pawl configuration by a plurality of such elements being joined together.
The freewheel arrangement according to the invention preferably has a maximum of three pawls, most preferably only one single pawl.
In order to ensure that the pawl is always ready, uninfluenced by centrifugal force effect, for locking interaction with the associated blocking surface, a preloading element preloads the at least one pawl into a blocking position.
It is then possible for the preloading element to be elastically deformable and fixed on the first element, and for the preloading element to interact with the at least one pawl in a recess region formed between two pawl plate elements.
The present invention relates, furthermore, to a freewheel arrangement, in particular for a guide wheel of a hydrodynamic torque converter, which freewheel arrangement essentially permits a relative rotation between two elements in only one rotational direction with respect to one another about an axis of rotation. A single pawl is pivotably supported on a first of the two elements and has a pawl section which can come into contact with a blocking surface of the second of the two elements.
The present invention relates, furthermore, to a hydrodynamic torque converter, which has a freewheel arrangement according to the invention. A plurality of guide wheel vanes sequential to one another in the peripheral direction is supported on one of the two elements in a radially outer region and the other of the two elements is supported so as to be rotationally fixed relative to a support element.
Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.